This DTC is stored when LIN communication between the certification ECU (smart key ECU assembly) stops for 10 seconds or more.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | DTC Output from | Priority |
|---|---|---|---|---|---|
| B278588 | Communication between ECUs connected by LIN Bus off | No communication between ID code box (immobiliser code ECU) and certification ECU (smart key ECU assembly) for 10 seconds or more. | ·
Certification ECU (smart key ECU assembly) ·
ID code box (immobiliser code ECU) ·
Wire harness or connector |
Entry&Start | A |
Before performing the inspection, check that DTC B278187 or B278C87 is not output.
When using the GTS with the ignition switch off, connect the GTS to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Entry&Start(CAN). While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.
Before replacing the certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU), refer to Service Bulletin.
Pre-procedure1
Disconnect the E52 certification ECU (smart key ECU assembly) connector.
Disconnect the E55 ID code box (immobiliser code ECU) connector.
Procedure1
Measure the resistance according to the value(s) in the table below.
Make sure that each ECU is in sleep mode before performing the inspection. To enter sleep mode, turn the ignition switch from ON to off and wait for 180 seconds or more without operating any switches.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
|
Click Location & Routing(E52,E55)Location & Routingewd_type=routing;type=c,c;code=E52,E55 Click Connector(E52)Instrument Panel>Instrument Panel Wire / Radio Wiring Sub-Assy / Telephone Computer Wire>Smart Key ECU Assemblyewd_type=component;type=c;code=E52;pinno=8 Click Connector(E55)Instrument Panel>Instrument Panel Wire / Radio Wiring Sub-Assy / Telephone Computer Wire>ID Code Box (Immobiliser Code ECU)ewd_type=component;type=c;code=E55;pinno=2 |
||
| E52-8 (LIN) - E55-2 (LIN1) | Ignition switch off | Below 1 Ω |
| E52-8 (LIN) or E55-2 (LIN1) - Body ground | Ignition switch off | 10 kΩ or higher |
| Proceed to |
|---|
| OK |
| NG |
Post-procedure1
None
OK
NG
Connect the E52 certification ECU (smart key ECU assembly) connector.
Check for DTCs.
Recheck for DTCs.
| Result | Proceed to |
|---|---|
| B278588 is output | A |
| B278588 is not output | B |
A
B